Yes, the larger the gauge the smaller the needle size.
Inserts a needle at the wrong angle or uses a large-bore needle
19
410
18g
0.474 (smallest they ever made i think)
A single needle prick obviously.
1.2mm / 16g
You cannot chop a tree down with a knitting needle as the needle does not have a sharp edge. You could bore it down if you lived long enough.
The size of a hollowed out sewing needle or small syringe
The smallest gauge needle that I'm aware of is 22g. But no one will pierce you with anything less than 20g, and that's usually in the nose. But, the standard size piercing needle is around 16-12g, but you can make a request to be pierced at a larger gauge, if there's sufficient flesh for it to go through.
The smallest book in the Library of Congress is called Old King Cole. The book is so small that its pages can only be turned with a needle.